Techniques of utilizing a laser beam emitted from a laser element for a vehicle-mounted light source device, in particular, a headlamp, have hitherto been known (see Patent Documents 1 to 3 listed below).
Patent Documents 1 and 2 both disclose a technique of using a laser beam as a phosphor exciting light. That is, in these techniques, a phosphor is irradiated with and excited by a laser beam emitted from a laser element to utilize the obtained fluorescent light as headlight.
Patent Document 3, on the other hand, discloses a technique of producing a white laser by combining colored laser beams emitted from laser elements that each emit red, green, and blue laser beams, to utilize this white laser as headlight.